I have an MSI Radeon HD 7970 video card that has 1 DVI, 1 HMDI, and 2 mini Display ports on it. I have one 24" ASUS Monitor plugged in via DVI, a 24'' Sansui Flatscreen plugged in via HDMI, and both are showing output and everything was great. But I purchased a third 24" ASUS monitor and tried hooking it up to my pc via one of the Mini Display ports with a mini DP - HDMI adapter. However this doesn't work and my third monitor isn't showing any output at all for HDMI. In catalyst control center, It recognizes the third monitor, but it's disabled and I can't use it without disabling one of the other monitors. Anyone know what I'm messing up on? Thanks.